$$\frac{dy}{dx}\left(\frac{y^2-1}{x^2-1}\right)$$

$$y=\left(\frac{x}{3}-1\right)^{-9}$$

$$\int\frac{x+2}{x^2+7x+12}dx$$

$$9w+8=80$$

$$\lim_{x\to100}\left(\frac{6.7x}{100-x}\right)$$

$$\int\left(\left(2x+9\right)^2\right)dx$$

$$\int_0^6\left(3x-7\right)\left(2x+1\right)dx$$